| ( | 4 | x | + | 3 | ) | ( | 5 | − | x | ) | = | 0 |
| Left side of the equation = | 4 | x | ( | 5 | − | x | ) | + | 3 | ( | 5 | − | x | ) |
| = | 4 | x | × | 5 | − | 4 | x | x | + | 3 | ( | 5 | − | x | ) |
| = | 20 | x | − | 4 | x | x | + | 3 | ( | 5 | − | x | ) |
| = | 20 | x | − | 4 | x | x | + | 3 | × | 5 | − | 3 | x |
| = | 20 | x | − | 4 | x | x | + | 15 | − | 3 | x |
| = | 17 | x | − | 4 | x | x | + | 15 |
| 17 | x | − | 4 | x | x | + | 15 | = | 0 |
| x1= | - | 3 4 |
| x2=5 |